Sports bats, such as baseball bats, tee-ball bats or softball bats, must be sufficiently strong and durable to withstand the impact of a ball against the bat during play. Additionally, the bats should possess an appropriate amount of stiffness in order to provide the desired performance characteristics.
Originally, baseball bats were made of wood. Wood ball bats provide many beneficial features, however, they are prone to failure, and can be too heavy for younger players even at reduced bat lengths. Metal bats, such as aluminum alloy bats, were introduced as being more durable than wooden bats. However, metal bats are much more expensive than traditional wooden bats. Further, many metal bats were susceptible to dents and corrosion, and further lacked the superior “feel” of wooden bats. Later, ball bats formed of layers of fiber composite material were introduced. These bats also provide many advantageous features, but are generally very expensive, and therefore are simply not practical for many younger players.
Many metal bats and many composite type bats transfer vibrational and shock energy from the barrel portion of the bat to the handle portion of the bat, thereby producing an undesirable sting or vibration to the user's hands. Many players, particularly younger players, have difficulty hitting or do not enjoy hitting due to such unpleasant vibrational feedback.
Ball bats have also historically been made of a plastic material, such as a traditional “wiffle” type ball bat. Despite providing some advantages such as a low cost and light weight, these plastic bats still possess many drawbacks. For example, existing plastic or wiffle-style bats are simply not configured for organized competitive baseball or softball play. Rather, “wiffle” type bats are configured for impacting traditional, lightweight, plastic wiffle balls only. Such bats are generally not configured to withstand an impact with an actual baseball or softball. Such bats are typically blow-molded, which is an expensive process compared to injection molding; furthermore, the process of blow molding is limited to a narrower range of materials compared to injection molding.
Other plastic bats may be formed from an injection molding process. Although injection molding is an efficient, economical process, it can be difficult to use injection molding to produce a one-piece bat. Bats require a uniform thickness, particularly in a barrel section, in order for the bat to perform consistently. It is difficult to maintain the alignment of a one-piece bat having a circular cross-section along an entire length of the bat during the injection molding process. Some plastic bats are injection-molded in two or more parts, thereby adding to the complexity and often the price of the bat.
It would thus be desirable to provide a sports bat that is strong and durable and possesses desired performance and feel characteristics without being prohibitively expensive. What is needed is a lightweight, durable bat that provides exceptional feel characteristics particularly for younger players at an affordable price. It would also be desirable to provide a method of forming such a bat in an injection molding process without alignment difficulties.